#include<iostream>
#include<cstring>

using namespace std;

class Cal
{
    public:
    Cal(){}
    Cal(double a,double b):m_a(a),m_b(b){}

    virtual double get_result() = 0;

    double m_a;
    double m_b;
};

class Add :public Cal
{
    public:
    Add(double a,double b):Cal(a,b){}

    double get_result()
    {
        return m_a + m_b ;
    }

};


int main()
{
    double a;
    double b;
    string op;
    cin>>a;
    cin>>op;
    cin>>b;
    Cal * cal;
    
    if(op == "+")
    {
        cal = new Add(a,b);
        cout<<cal->get_result()<<endl;
    }





}



